An elevator has an elevator car moving up and down in an elevator shaft. During operations of the elevator, an elevator control device needs to determine the location of the elevator car in the elevator shaft in real time, thereby controlling the operations of the elevator car based on the location information. Therefore, location information of an elevator system is the basic information for the operations of the elevator, and the location of the elevator car needs to be constantly recognized during the operations of the elevator.
However, during operations of an elevator, there is a case where the location information of the elevator car is lost, for example, due to temporary power-off of the elevator system. In this case, there is a need to recover the location information of the elevator system as soon as possible.
At present, when the location of an elevator system is lost or the current location information is invalid, an elevator control device generally controls and drives the elevator car to the bottom or the top of the elevator shaft, so that the location information of the elevator system is re-calibrated and the elevator control device obtains valid location information.